1. Field of the Invention
The invention relates to a solenoid, in particular, for actuating a hydraulic valve of a motor vehicle, that comprises a pole core delimiting an armature chamber, wherein an armature is slidingly movable in the armature chamber and wherein a minimal axial spacing of the armature relative to the pole core is determined by an anti-stick disc. The solenoid further comprises an armature piston that is received in a central receptacle of the armature and extends through a central bore of the pole core, preferably with formation of a radial gap, wherein the armature piston is preferably made of nonmagnetic material and is used to actuate a valve member when acted on by the armature.
2. Description of the Related Art
Such a solenoid is, for example, known from the German patent document 197 17 445 A1 or the German patent document 195 04 185 A1. In these solenoids the armature piston is produced of solid rod material that has nonmagnetic properties. Between the facing end faces of the armature and the pole core an anti-stick disc is arranged which surrounds the armature piston and whose thickness defines a minimal axial air gap between the armature and the pole core. The anti-stick disc is a separate part and must be threaded onto the armature piston and mounted together with the armature and the armature piston, the latter being pressed into a blind bore of the armature. Overall, the manufacture of the individual parts and their assembly are complex and expensive.